The TAG is trying to learn more about Web Services Addressing and its
likely uses. To further our investigations, TAG member Henry Thompson set
out to create a representative example of Endpoint Reference use, based
primarily on what he could learn from publicly available sources. Note
that Henry claims no deep expertise in WSA, and indeed is trying to learn
by doing. Henry's first pass at an example is at [1] (advertised in email
at [2]). In part because it contained both samples and a toolkit, Henry
chose to use the Apache WSRF toolkit [3] as the basis for his work.
The TAG would very much appreciate guidance as to whether this is an
appropriate first example from which to learn, and if not, where we might
look to find something more representative. Among the specific questions
and concerns that have arisen are:
* If we want to understand typical uses of EPRs, are we doing the right
thing to start with WSRF-based examples or are there others we should
consider first?
* Given that the example is WSRF-based, there is some confusion as to
where the EPR would have come from, and the degree to which the EPR would
in practice be opaque to the client. In other discussions it has been
suggested that EPRs are typically returned from a service provider and
are, except insofar as the SOAP binding requires them to be re-expressed
as headers for transmission, opaque to the client.
* Is it typical to have an operation such as sq:TradePriceRequest, as in
Henry's example, or would it be more common to have a more generic
GET-like operation such as GetResourceProperty [4]?
* The likely use of WSDL with EPRs is still somewhat unclear to us.
Henry's example does provide some WSDL, but it's not entirely clear how
its use relates to Web Services addressing.
The TAG is holding a F2F meeting on Monday and Tuesday Dec. 5 and 6. For
the moment, it will be more useful to have early informal input than to
have a later formal response from the Web Services Addressing Workgroup.
Any guidance that you can provide us would be much appreciated.
Thank you.
Noah Mendelsohn
- for the W3C Technical Architecture Group
[1]
http://lists.w3.org/Archives/Public/www-tag/2005Nov/att-0008/eprExample.html
[2] http://lists.w3.org/Archives/Public/www-tag/2005Nov/0008.html
[3] http://ws.apache.org/wsrf/
[4]
http://docs.oasis-open.org/wsrf/2004/11/wsrf-WS-ResourceProperties-1.2-draft-05.pdf
--------------------------------------
Noah Mendelsohn
IBM Corporation
One Rogers Street
Cambridge, MA 02142
1-617-693-4036
--------------------------------------